Exhibit 21.1

Subsidiaries List (as of 12/31/2006)

|Name:                                                       |  | Percent Owned by SST:                                                                                                                                                |  | Jurisdiction of Organization:
|----------------------------------------------------------- |  | -------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | -----------------------------
|SST RG, LLC                                                 |  | SST - 100% sole membership interests                                                                                                                                 |  | Delaware                     
|SST Japan K.K.                                              |  | 100% owned by SST                                                                                                                                                    |  | Japan                        
|Silicon Storage Technology Limited (UK)                     |  | 100% owned by SST                                                                                                                                                    |  | England and Wales            
|SST Communications Corporation                              |  | 100% owned by SST                                                                                                                                                    |  | Delaware                     
|SST Communications, Ltd.                                    |  | 100% owned by SST Communications Corporation                                                                                                                         |  | Cayman Islands               
|SST Communications Company                                  |  | 100% owned by SST Communications, Ltd.                                                                                                                               |  | Taiwan                       
|SST International Limited                                   |  | 100% owned by SST                                                                                                                                                    |  | Cayman Islands               
|SST International Limited 1                                 |  | 100% owned by SST International Limited                                                                                                                              |  | Cayman Islands               
|SST International Limited 2                                 |  | 100% owned by SST International Limited                                                                                                                              |  | Cayman Islands               
|SST International Limited 3                                 |  | 100% owned by SST International Limited                                                                                                                              |  | Cayman Islands               
|SST Taiwan Ltd.                                             |  | 100% owned by SST International Limited                                                                                                                              |  | Cayman Islands               
|SST Korea Ltd.                                              |  | Owned by SST International Limited                                                                                                                                   |  | Korea                        
|SST International Macao Commercial Offshore Company Limited |  | 100% owned by SST International Limited                                                                                                                              |  | Macao                        
|SST Hong Kong Limited                                       |  | Owned by SST International Limited & SST International Limited 1 - 2 shareholders (50%)                                                                              |  | Hong Kong                    
|Silicon Storage Technology Taiwan Ltd.                      |  | Owned by SST International Limited (96%), SST International Limited 1(1%), SST International Limited 2 (1%), SST International Limited 3 (1%) & SST Taiwan Ltd. (1%) |  | Taiwan                       
|SST China Holding Ltd.                                      |  | 100% owned by SST International Limited                                                                                                                              |  | Cayman Islands               
|SST China Ltd.                                              |  | 100% owned by SST International Limited                                                                                                                              |  | China                        
|Actrans Systems Inc.                                        |  | 100% owned by SST International Limited                                                                                                                              |  | Taiwan                       
|Actrans System Incorporation, USA                           |  | 100% owned by Actrans System Inc.                                                                                                                                    |  | California                   
|SST Singapore Pte. Ltd.                                     |  | 100% owned by SST International Limited                                                                                                                              |  | Singapore                    
|Emosyn International Limited                                |  | 100% owned by SST International Limited                                                                                                                              |  | Cayman Islands               

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